Oil, along with many other fluid products, is often moved through pipes from origin to destination. Valves are used in the pipeline to control the flow of fluid. Valves, long known in the art, are generally comprised of: a body or outer casing; a disk which is a movable obstruction inside the body that adjustably restricts the flow through the valve; a stem attached to the disk to control the placement of the disk and flow of product; a handle or wheel to turn the stem and open and close the valve; a bonnet to hold the parts within the body; ports to allow passage of fluid through the valve; a seat which is an interior surface of the body which contacts the disk to form a seal and prevent fluid from passing through the valve; packing which is used to prevent the leak of fluid from the valves; and a gland which exerts pressure on the packing to hold the packing in place and prevent fluid leakage around the stem. The handle rotates the stem which moves the disk into and out of engagement with the seat. When the disk is completely engaged with the seat, the movement of fluid through the valve is fully restricted. As the disk is disengaged from the seat, fluid passes through the valve. The further the disk is disengaged the more fluid passes through the valve.
The stem of the valve is commonly covered by a yoke tube which may or may not include packing. Packing is used to prevent fluid from traveling up the stem and exiting the valve. Current state of the art valves employ a single packing chamber, often located in the yoke tube, to assist in sealing the stem and preventing fluid leaks. If the packing fails, nothing remains to prevent fluid from traveling up the stem and entering the environment.
Thus, there exists a need for a better packing system which will reduce the risk of environmental exposure of the fluid.
There is a further need for a cost effective packing system that can be added to existing valves in existing pipelines without incurring the exhorbitant and needless cost of replacing the entire valve.